Electrical gauging means



May 31, 1966 T. c. BURNETTE, JR 3,253,338

ELECTRICAL GAUGING MEANS Filed Feb. 8, 1962 2 Sheets-Sheet l ATTORNEYS May 31, 1966 Filed Feb. 8, 1962 T. C. BURNETTE, JR

ELECTRI CAL GAUGING MEANS 2 Sheets-Sheet 2 75 0 FIN 744,

a o 7i g8 m56 INVENTOR. T/AoDEz/s C. c/@A/ErrgJz BY Arme/lays United States Patent C) 3,253,338 ELECTRICAL GAUGING MEANS Thaddeus C. Burnette, Jr., Asheville, N.C., assigner to C. P. Clare 8: Company, Chicago, Ill., a corporation of Delaware Filed Feb. 8, 1962, Ser. No. 171,893 Claims. (Cl. 33-169) This invention relates to a switching assembly and, more particularly, to a new and improved switching assembly using sealed switch units and an electrical gauging apparatus embodying the switching means.

In many different types of equipment, it is necessary to determine whether the dimensions of an article fall within certain predetermined ranges of value. For example, many manufacturing operations include a gauging step in which the manufactured article is checked to determine whether certain dimensions of the article fall within a given tolerance range. also includes means for determining the values of tendered coins by gauging the sizes thereof.

In some types of coin handling equipment, a switching assembly is provided in which a wiper is moved relative to a plurality of fixed contacts under the control of the displacement of a gauging element that is moved into engagement with a coin passing through a coin inlet or gauging station. In this type of gauging apparatus, the acceptable range of dimensions for each different size of coin is established by the size or width of the xed contact individual to each coin. However, there are a number of deficiencies in this method of measuring article dimensions. y

In order to obtain the necessary discri-mination between coins of different sizes and to insure electrical contact in only the range between the lowest and highest acceptable dimensions for each coin, it is necessary to provide a considerable amount of movement or mechanical arnpliiication between the gauging element and the switching assembly. This is necessary because the amount of displacement of the gauging element produced by coins of different sizes is rather small compared to the movement required to provide acceptable discrimination in the switching means. This movement amplification means results in increased pressures on the gauging element and introduces large moving masses interposed between the gauging element and the switching means which not only reduce the response speed of the gauging system but also the accuracy thereof. In addition, the exposure of the fixed contacts to atmospheric conditions and mechanical abrasion reduces the reliability and operating life of the switching means.

Accordingly, one object of the present invention is to provide a new and improved switching assembly.

Another object is to provide a switching assembly including a plurality of sealed switch units with their gaps spaced in a given direction and permanent magnetic means movable in said given direction to selectively operate the switch units.

A further object is to provide a switching assembly including both a plurality of sealed switch units mounted in a circular array with their gaps spaced axially along the opening formed by the circular array and permanent magnetic means movable along the axis of the opening to different positions to operate different ones ofA the switch units. v

Another object is to provide a gauging system providing an electrical output which does not require mechanical amplifying means.

Another object is to provide an electrical gauging system using sealed switch units actuated by permanent magnetic means to provide greater contact reliability and life.

Coin handling apparatus 3,253,338 Patented May 31, 1966 FCnce Another object is to provide an electrical gauging vapparatus in which the gaps of a plurality of sealed switch units are spaced different distances from each other in a given direction corresponding to the dimensional ranges of articles to be gauged and in which a permanent magnetic means is moved in said given direction to operate different ones of the switches to indicate the dimension of the gauged article.

In accordance with these and many other objects, a switching assembly embodying the invention comprises a plurality of sealed switch units supported in a circular array to provide an axially extending opening in which is disposed an axially movable permanent magnet. The sealed switches are displaced from each other along the axis of the opening so that the gaps formed by the magnetic elements therein are spaced from each other in an axial direction. When the permanent magnet is moved to different axially spaced positions by an operating means connected thereto, different ones or combinations of the sealed switch units are operated in dependence on the position of the permanent magnet.

In one embodiment of the invention, the plurality of sealed switch units are divided into two separate groups, one of which has their gaps disposed .adjacent the normal position of the permanent magnet so that the magnetic elements are held in engagement to complete electric circuits therethrough. The other group -of sealed switch units are disposed with their gaps spaced from the normal position of the permanent magnet so that the magnetic elements are not engaged. When the operating means for the switching assembly is actuated to move the permanent magnet from its normal position to a displaced position adjacent the gaps in the second group of switch units, the contacts in the rst group of switch units are opened and the contacts in the second group of Switch units are closed. By controlling the spacing of the gaps in the two groups of switch capsules and the strength and coniiguration of the field of the permanent magnet, the switching assembly can either provide a plurality of transfer or type C contacts or a plurality of make-before-break or type D contacts in which the normally openswitch capsules in the second group are operated to a closed condition prior to the release of the normally operated switches in the first group.

In another embodiment of the invention providing an electrical gauging system, the gaps in the plurality of sealed switch units are axially displaced from each other distances proportional to the dimensions of the articles to be gauged, and the operating means connected to the permanent magnet is connected to a gauging element or surface that is adapted to engage an article, such as a coin. The deflection of the gauging element displaces the permanent magnet in an axial direction relative to the spaced gaps and operates 4a particular one or combination of the sealed switch units in dependence on the degree of movement to provide an indication of the size of the gauged article.

The strength and configuration of the magnetic iield provided bythe permanent magnet and the spacing of the gaps in the sealed switch units can be such that the permanent magnet is shifted in direct response to the engagement of the gauging element by the article and without the use of intervening movement amplifying means. The sensitivity of this arrangement is such that mechanical displacements in the order of thousandths of an inch can be directly measured and indicated. The sealed switches protect the contact elements from atmospheric contamination and are free from the adverse effects of mechanical abrasion. Further, since the sealed switches are operated by moving the permanent magnet rela-tive to these switches without the use of `an intervening mechanical amplifying means, the pressure 4applied to the -.article to tbe gauged is reduced to a minimum, and the system responds quickly to displacement of the article engaging element.

Many other objects and advantages of the present invention will become apparentfrom considering the following detailed description in conjunction with the drawings, in which:

FIG. 1 is a perspective view, in partial section, of a switching assembly embodying the present invention;

FIG. 2 is a sectional view taken along line 2-2 in FIG. 1;

FIG. 3 .is a sectional view taken along line 3 3 in FIG. 2;

FIG. 4 is an enlarged sectional view taken along line 4-4 in FIG. 2;

FIG. 5 is an end view of the switching assembly;

FIG. 6 is a schematic view of a coin gauging apparatus embodying the switching assembly of the present invention;

FIG. 7 is a sectional view of the switching assembly used in the apparatus shown in FIG. 6;

FIG. 8 is a sectional view taken along line 8 8 in FIG. 7;

FIG.` 9 is ran enlarged sectional view taken along line 9-9 in FIG. 8 illustrating the switching assembly in a normal condition;

FIG. 10 yis a sectional view similar to FIG. 9 illustrating the switching assembly in a first operated condition;

FIG. 11 is a sectional view similar to FIGS. 9 and l0 illustrating the switchingv assembly in a second operated condition; and

FIG. 12 is a circuit diagram illustrating one indicating means that can be used in the gauging apparatus shown in FIG. 6.

Referringnow more specifically to FIGS. 1-5 of the drawings, therein is illustrated a switching assemlbly, indicated generally as 20, which embodies the present invention and which includes a plurality of sealed switch units 22 supported `in a circular array to define .an axially extending central opening. Each of the sealed switch units 22 includes `a pair of magnetic elements forming a gap, and the plurality of sealed switch units 22 are divided into two groups 22a and 212]) mounted with their gaps spaced from' each other along the axis of the central o-pening. A permanent magnet 24 is slidably mounted in the central opening and is normally retained in a position adjacent the gaps in the sealed switch units 22a to hol-d the magnetic elements therein in a closed condition completing a conductive circuit.

When the permanent magnet 24 is displaced from a position adjacent the gaps iny the switch units 22a to a position adjacent the gaps in the Switch units 22b, the magnetic elements Vin the switch units 22a separate to interrupt the conductivev circuits therethrough, and the magnetic elements in the switch units 2217 aremoved into engagement to complete conductive circuits therethrough. In this manner, the staggering or spacing of the gaps in the two groups of switch units 22a and 22b and the axial movement of the permanent magnet 24 in the direction in which the gaps are spaced permit the selective operationrof `different groups of the sealed switch units 22 in response to an axial displacement of the permanent magnet 24. As illustrated in FIGS. 1-5, the switching assembly can comprise a manually actuated key.

Each of the sealed switch units 22 can -comprise one 0f the well known sealed switch constructions, such as a mercury wetted contact switch or a dry type contact switch. The illustrated switch units 22 are dry type or magnetic reed switches including an elongated dielectric or glass envelope 26 from the opposite ends of which a pair of magnetic reed elements or terminals 28 and 30 extend. The inner ends of the magnetic elements 28 and 30 are provided with overlapping portions 28a and 30a that are normally maintained in a spaced relation to dene a gap. When a magnetic field of sufcient strength is applied to the magnetic elements 28 and 30 in the vicinity of the gap, the overlapping portions 28a and 30a are exed `or deected to move into enga-gement to complete a conductive circuit through the sealed switch unit 22. The magnetic elements 28 and 30 are moved out of engagement by the inherent resilience of these elements when the applied magnetic field is removed.

The plurality of sealed switch units 22 are supported in a circular arrangement or array by a pair of circular dielectric supporting plates or elements 32 and 34 to define an axially extending opening 36. The lower ends of the switch units 22 are mounted on the supporting plate 34 by inserting either flattened terminal portions 30h of the elements 30 in the switch units 22b or terminal extensions 38 that are secured to the terminal portions 30b of the elements 30 in the switch units 22a into slots in the supporting plate 34. Upper terminal portions 28h (FIG, 4) of the elements 28 on the switch units 22a are arcuately formed and connected to an upper end of an electrically conductive and nonmagnetic connector or supporting element 40. The terminal portions 28h of the magnetic elements 28 in the switch units 22b are also connected to the upper portions of the elements 40. The

ing assembly 20 to external circuits.

In the embodiment of the switching lassembly 20 shown in FIGS. 1-5, the supporting or connector` elements 40 not only support the pairs of sealed switch units 22a and 22b but also provides a common electrical connection to the terminals 2811 thereof. 'If' desired, the element 40 could be formed of a dielectric material with a conductive layer or printed circuit on opposite sides thereof to which the terminal portions 28h of the magnetic elements 28 in the switch units 22a and 22b can be connected. In 'this manner, separate electrical connections can be made to the magnetic elements 28 in the two sealed switch units 22a and 22b.

To provide means for lguiding axial movement of the permanent magnet 24, a dielectric sleeve or tube 42 is disposed in the axial opening 36 defined by the sealed switch units 22 with its lower end resting on the upper surface of the supporting plate 34. The upper end of the tube 42 is secured to the lower surface of the upper supporting plate 32. A compression spring 44 interposed between the upper surface of the plate 34 and the lower end of the permanent magnet 24 provides means for normally holding the permanent magnet 24 in its normal position adjacent the gaps provided by the magnetic 4elements 28 and 30 in the sealed switch units 22a (FIG. 4) and spaced from the gaps dened by the magnetic elements 28 and 30 in the sealed switch units 22b. The other end of the permanent magnet 24 preferably is provided with a recess in which is secured the lower end of a dielectric and nonmagnetic operating shaft 46. This shaft extends through a bushing 48 which is mounted in a centrally disposed opening in the upper supporting plate 32 and which is provided at its upper end with a knob 50. A circular lock spring `SZ carried in a groove on the shaft 46 engages the lower end of the bushing 48 to limit upward movement of the permanent magnet 24 by the compression spring 44 and determines the normal position of this permanent magnet.

The switching assembly `20 is provided with an ex ternal housing 54 formed of a dielectric material and having an open lower end and an upper wall having an opening v56. When the sealed switch units 22 and the supporting and operating means therefor are to be mounted on the housing 54, an externally threaded portion 48a of the bushing 48 is inserted through the openingd until .a ange48b on this bushing engages the lower surface of the upper wall of the housing 54. A nut 58 is then threaded on the portion 48a to secure the switching assembly in position within the housing 54. ln this assembled position, the circular supporting plate 34 closes the lower end of the housing 54.

As indicated above, the compression spring 44 and the lock spring 52 normally hold the permanent magnet 24 in a position disposed adjacentl the gaps formed by the overlapping portions 28a and 30a of the magnetic elements 28 and 30 in the sealed switch units 22a so that these magnetic elements are held in `engagement to complete conductive circuits between the terminal extensions 318 and the connector elements 40. The permanent magnet 24 is spaced from the gaps formed by the overlapping portions 28a and 30a of the magnetic elements 28 and 30 -in the switch units 22b. Thus, conductive circuits are not completed between the connector elements 40 and the terminal portions 30b in the switch units 2217. When the switching assembly 20 `is operated, the knob 50 is depressed to the position shown in dot and dash outline in FIG. 3 to move the permanent magnet 24 downwardly to a position in which it is spaced from the gaps in the switch units 22a and is adjacent the gaps inthe switch units 22h. This permits the magnet elements 28 and 30 in the switch units 22a to separate and interrupt the conductive circuits through the switch units 22a and moves the elements `28 and 30 in the switch units 22b into engagement to complete conductive circuits'through the switch units 2211. The compression spring 44 restores the permanent magnet 24 to its normal position when the knob 50 is released, and the switching assembly 26 returns to its normal condition in which conductive circuits are completed through the switch units 22a and are not completed through the switch units 22b.

By suitably adjusting the axial spacing of the gaps in the switch units 22a and 22b and by controlling the conguration and strength Iof the magnetic field provided |by the permanent magnet 24,each pair of switch units 22a and 22h can provide either type C'or type D contacts. If the gaps in the switch units 22aand 22h are positioned more closely together alongA the axis` of the opening 36 or if the strength of the permanent magnet 24 is increased, the contacts provided by the magnetic elements 28 `and 30 in the switch units 22h will close to complete conductivecircuits prior to the opening or separation of the magnetic elements 28 and 36 in the switch units 22a. This provides a type D or make-before-break contact arrangement. Alternatively, if the axial spacing of the gaps in the switch units 22a and 2-2b is increased or if the effective strength of the permanent magnet 24 is decreased, the switch units 22u open before the switch -units 2211 operate, and each pair of switch unitsl 22a and 22h provides 'a normal transfer or type C contact arrangement.

FIGURE 6 of the drawings illustrates an electric gauging system, indicated generally as 60, which embodies the present invention and which provides an indication of the sizes of different articles. The gauging apparatus 60 includes a switching assembly 62 that is similar to the switching assembly 20 in including a plurality of sealed switch units whose gaps are displaced relative to each other in a given direction `a distance proportional' to the different acceptable dimensions of the articles to be gauged. The .switching assembly 62 also inclu-des a perg manent magnet connected to a slida'ibly mounted operating shaft 64 that is connected to a gauging element or roller 66 which extends into an article feeding passageway, such as a coin inlet 68, through an opening 70. The coin engaging roller 66 is displaced to the right or left a distance corresponding to the diameter of the coin advanced through the inlet 68 and produces a corresponding displacement of the permanent magnet in the switching assembly 62. The position to which the permanent magnet is adjusted within the switching assembly 62 closes a selected switch Iunit or combination of switch units to electrically control an indicating assembly 72 to provide an indication of the size of the sensed article. The displacement of the gaps of the sealed switch units used in the assembly 62 permits the permanent magnet to be directly connected to the article engaging roller 66 without the need for an intervening mechanical arnplifying means, and the apparatus 66 is capable of detecting displacement on the order of thousandths of an inch. The sealed switch units used in the assembly 62 possess great reliability and an oper-ating life far in excess of other switching arrangements.

FIGURES 7-11 illustrate the details of one switching assembly that can be used in the electrical gauging system 60. The assembly 62 is similar to the switching assembly 20 in including a plurality'of se-aled switch units 74 which are supported in a circular arrangement by the two dielectric supporting plates 32 and 34 surrounding the axial opening in which the dielectric tu'be 42 containing the permanent magnet 24 and the inner end of the nonmagnetic shaft 64 is disposed. The permanent magnet 24 is connected to the inner end of the shaft 64.

The sealed switch units 74 can be substantially identical to the sealed switch units 22 and include a dielectric envelope 76 containing a pair of magnetic elements 78 and 80 with overlapping inner end portions 78u and 80a normally defining a gap and operable into engagement to complete an electric circuit in response to the application of a magnetic eld. A terminal portion 80h on the magnetic element 80 is either directly inserted into a slot in the .supporting plate 34 or connected to a terminal extension 38 that is received within the slot in the supporting plate 34. A terminal portion 78h on the magnetic element 78 is secured to one of a plurality of nonmagnetic and electrically conductive supporting elements 82. If desired, the terminal portions 78h on the magnetic elements 78 in a pair of adjacent switch units 74 could be connected to a single element 82 in the same manner in which the vterminals 28b are connected to the common supporting and conducting element 40 in the switching assembly 20.

However, the sealed switch units 74 are mountedon the supporting plates 32 and 34 in the switching assembly 62 in a slightly different manner than in the switching assembly 20. In the assembly 20, the sealed switch units 22 are divided into two separate groups with their gaps disposed in only two Iaxially spaced positions. In the switching assembly 62, the switch units 74 are supported in a plurality of different positions spaced along the axis of the tube 42 or the path of movement of the permanent magnet 24 in accordance with the different dimensions of the articles or coins to be inserted into the passageway 68. As an example, a single sealed switch unit 74 could be supported with its gap disposed adjacent each of the diierent positions occupied by the v permanent magnet 24 corresponding to the different sizes of the coins inserted into the inlet 68.

In FIGS. 7-11 of the drawings, the sealed switch units 74 are disposed in a different arrangement in which a pair of sealed switch units 74a and 74b is provided for detecting the size of eac-h coin. In each pair of sealed switch units 74a and 74b, the gap in the sealed unit 74a is disposed in a position such that this switch will not be operated by the permanent magnet 24 when the article engaged by the roller 66 is smaller than a size or range of sizes acceptable for a given coin, such as a nickel. The switch unit 74b is mounted with its gap in a position such that this switch will not be operated by the permanent magnet 24 when ythe roller 66 engages anarticle larger than a size or range of sizes acceptable for the same coin. Therefore, when the permanent magnet 24 is moved to a position between the gaps in the switch units 74a and 74b, both of the switch units 74a and 74b are operated to indicate that the size of the coin is within the expected dimensional range and that the coin has a known value. erates only one of the switch units 74a and 74b, the article inserted into the guide 68 is not within the accepted range and is not a coin of the given value.

FIGURE 12 of the drawings illustrates one circuit that can be used in Ythe indicating means 72 in combination with one pair of sealed switch units 74a and 74b to indicate whether an article falls within an expected dimensional range and is a coin of a given value. The magnetic c-ontacts or elements 78 and 80 in the twio sealed switch units 74a and 74b are connected in series between a potential source, such as a battery 84, and an. ndicator lamp 86. The lamp 86 is energized by the potential source 84 only when both of the switches 74a and 74b are operated to indicate that a gauged article is within the expected dimensional range.

In operation, a coin is inserted into the coin inlet 68 and engages the roller .66 so that the shaft 64 is displaced to position the permanent magnet 24 in the switching assembly 62 in an axial position determined by the diameter of the engaged coin. If the engaged coin is too small, the magnet 24 is disposed in the position shown in FIG. 9 in which the magnetic elements 78 and 80 in only the switch unit 74b are closed. Thus, the lamp 86 is not illuminated to indicate that the coin isnot of the given value. If the size of the inserted coin is within the tolerance range, the shaft 64 and t-he permanent magnet 24 are moved to the position shown in FIG. 10 in which the magnetic iield of the magnet 24 moves the-magnetic elements 78 and 80 in both of the switch units 74a and 74b into engagement. This completes a conductive circuit between the potential source 84 and the lamp 86 and illuminates this lamp to provide a visible indication that t-he coin has t-he given value. vIt the engaged coin is too large, the shaft 64 'and the permanent magnet 24 are moved to the posi` tion shown in FIG. 11 in which the field of the magnet 24 closes the magnetic elements 78 and 80A in only the switch -unit 74a. Thus, the circuit for the lamp 86'is not completed, and this lamp is not illuminated to provide an indication that the inserted object is not a coin of the given value. v

The switching assembly 62 includes a pair of switch units 74a'and '74b for each size coin that can be inserted into the coin inlet 68 (see FIG. 7). Each pair of the sealed switches 74 providesa positive indica-tion only when the article inserted into the inlet 68 falls within the known dimensional range. The acceptable range A of dimensions can be increased by moving the gaps in the switch uni-ts 74a and 74b further apart and by making a compensating change in the configuration and strength of the magnetic field of the permanent magnet 24. This ydimensional range can be decreased by moving the gaps of the switch units 74a and 74b-closer together in an axial direction and by making a corresponding reduction in the effective iield of the permanent magnet 24.

It is also possible to provide a pair of switching assemblies 62 actuated in common or parallel by the coin engaging roller 66. One of the switching assemblies 62 could contain all of the switch units 74b, and the other switching assembly 62 could contain all of the switch units 74a. Further, additional circuits could. be provided in the indicating means 72 controlled by the individual switches 74a and 74b for providing positive indications when an engaged article is undersize and oversize as well as within the accepted range.

Although the present invention has been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art than will fall within the spirit and scope of the principles of this invention.

What is claimed as new .and desired to be secured by Letters Patent of the United States is:

If the magnet'24 op- 4 1. An apparatus for gauging articles Afalling within a plurality of ranges between different high and low dimensions, a plurality of sealed switch units having magnetic elements defining gaps, supporting means mounting said sealed switch units in positions with the gaps spaced from each other in a given direction, said sealed switch units being mounted so that the gaps in different pairs of said switch units are spaced in said given direction distances proportional to the high and low dimensions of said plurality of ranges, permanent magnetic means disposed adjacent said switch units, operating means including means adapted to engage said article for moving said permanent magnetic means in said given direction a distance proportional to the size of the engaged article, and indicating means connected to the magnetic elements in said sealed switch units and responsive to the operation of both of the switch units in the pair representing a given range for indicating the size of the engaged article.

2. An apparatus for gauging articles having a size in a range between a lower dimension and a higher dimension comprising a pair of sealed switch units, each of said switch uni-ts including a dielectric housing containing at least a pair of magnetic elements spaced from each other to form a gap and operable by an applied magnetic eld to close said gap and `complete an electric circuit,

supporting means for supporting said pair of sealed switch units with their gaps spaced from each other in a given direction a distance corresponding to the difference between said higher and lower dimensions, permanent magnetic means disposed adjacent said sealed switch units, article engaging means adapted to engage an article to be gauged and including means for moving said permanent magnetic means in said given direction relative to the gaps in said sealed switch units, said permanent magnetic means operating different ones of said switch units when the engaged article is below or above said range and operating both of said switch units when said article falls Within Said range, and indicating means controlled by said pair of switch units for indicating whether the engaged article -falls within said range.

3. An apparatus for gauging articles having different sizes in ranges between lower dimensions and higher dimensions comprising a plurality of pairs of sealed switch units, each of said switch units including a dielectric housing containing at least a pair of magnetic elements spaced from each other to form a gap and operable by an applied magnetic field to close said gap and complete an electric circuit, supporting means for supporting .said pairs of sealed switch units' with their gaps spaced from each other in a given direction a distance representing the difference between the higher and lower dimensions for each range, permanent magnetic means disposed adjacent said sealed switch units, article engaging means adapted to engage articles to be gauged and including means for moving said permanent magnetic means in said given direction relative to the gapsin the sealed switchunits, said permanent magne-tic means operating different ones of said switch units when the engaged article is below or above said range and operating both of the switch units for a given range when the article falls within this given range, and indicating means controlled by said switch units for indicating whether the engaged article falls within a range and the range in which the engaged article does fall.

4. A switching assembly comprising a plurality of electrically conductive supporting members, a plurality of sealed switch units having elongated dielectric housings with magnetic terminals projecting yfrom their opposite ends, each pair of magnetic terminals having spaced portions defining a gap, means securing the magnetic terminals at one end of a pair of the sealed switch units to opposite sides of a supporting member, the gaps of the pair of sealed switches being spaced from each other along the length of the supporting member,'perma nent magnet means movable in a direction generally along the length of the supporting members between positions adjacent different ones of the gaps, and means for mounting the sealed switch units including a rst structure for engaging the supportingmembers at one end and -for engaging the supporting members and the other two magnetic terminals of each pair of sealed switches at the other end.

5. A switching assembly comprising a plurality of pairs of sealed switch unit-s each including an elongated dielectric housing with magnetic elements extending from its opposite ends, the inner ends of said magnetic elements being movable into and out of engagement to dene a gap, ysupporting means mounting said sealed switch units lin a circular array defining an axially extending opening, said supporting means mounting a first group of said sealed switch units with their gaps at a rst position relative to the axis of said opening and a second group of said sealed switch units with theirv gaps at a second position -spaced from said first position along said axis, said supporting means including a first dielectric supporting element at one end of said circular array and a second dielectric supporting element engaging the magnetic elements at the other end of the circular array, connecting means connected to the magnetic elements at said one end of said array and carried on said iirst and second supporting elements, said connecting means being electrically conductive and disposed between alternate ones of the sealed switch units extend-ing generally parallel thereto, each of said connecting means being disposed References Cited by the Examiner UNITED STATES PATENTS 2,287,363 6/1942 Weston 194-102 2,495,416 l/l950 McCauley 7.3-308 2,976,378 3/1961 Goddard 20G-87.3 2,978,556 4/1961 Lobs et al 200-87 3,051,805 8/1962 Binford ZOO-87.3 3,060,291 10/ 1962 Clare 20G-87.1":

OTHER REFERENCES Publication: lIndustrial and Engineering Chemistry, March 1947, page 263.

ISAAC LISANN, Primary Examiner.

R. E. KLEIN, N. F. MATTHEWS, Assistant Examiners. 

1. A SWITCHING ASSEMBLY COMPRISING A PLURALTIY OF ELECTRICALLY CONDUCTIVE SUPPORTING MEMBERS, A PLURALITY OF SEALED SWITCH UNITS HAVING ELONGATED DIELECTRIC HOUSING WITH MAGNETIC TERMINALS PROJECTING FROM THEIR OPPOSITE ENDS, EACH PAIR OF MAGNETIC TERMINALS HAVING SPACED PORTIONS DEFINING A GAP, MEANS SECURING THE MAGNETIC TERMINALS AT ONE END OF A PAIR OF THE SEALED SWITCH UNITS TO OPPOSITE SIDES OF A SUPPORTING MEMBER, THE GAPS OF THE PAIR OF SEALED SWITCHES BEING SPACED FROM EACH OTHER ALONG THE LENGTH OF THE SUPPORTING MEMBER, PERMANENT MAGNET MEANS MOVABLE IN A DIRECTION GENERALLY ALONG THE LENGTH OF THE SUPPORTING MEMBERS BETWEEN POSITIONS ADJACENT DIFFERENT ONES OF THE GAPS, AND MEANS FOR MOUNTING THE SEALED SWITCH UNITS INCLUDING A FIRST STRUCTURE FOR ENGAGING THE SUPPORTING MEMBERS AT ONE END AND FOR ENGAGING THE SUPPORTING MEMBERS AND THE OTHER TWO MAGNETIC TERMINALS OF EACH PAIR OF SEALED SWITCHES AT THE OTHER END. 